A non-amenable groupoid whose maximal and reduced C∗-algebras are the same
نویسنده
چکیده
We construct a locally compact groupoid with the properties in the title. Our example is based closely on constructions used by Higson, Lafforgue, and Skandalis in their work on counterexamples to the BaumConnes conjecture. It is a bundle of countable groups over the one point compactification of the natural numbers, and is Hausdorff, second countable and étale with compact unit space.
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تاریخ انتشار 2015